The invention relates to improvements in apparatus for transporting rod-shaped articles, such as plain or filter cigarettes, cigars or cigarillos, filter rod sections and other rod-shaped articles of the tobacco processing industry. More particularly, the invention relates to improvements in apparatus for transferring rod-shaped articles from a source of supply of substantially parallel articles into the inlet of a pneumatic conveyor wherein the articles form a single file of articles.
U.S. Pat. No. 3,827,757 discloses an apparatus wherein a rotary drum-shaped conveyor is employed to accept a series of rod-shaped articles from the outlet of a magazine and advances successive articles of the series to a position of alignment with the inlet of a pneumatic conveyor. A pneumatic ejector system is employed to propel successive rod-shaped articles from their flutes at the periphery of the rotary conveyor into the inlet of the pneumatic conveyor. The patented apparatus further comprises a stationary block-shaped sealing member which is installed at the ejecting station to engage the periphery of the rotary conveyor in the region where the articles are propelled into the inlet of the pneumatic conveyor. The purpose of the sealing member is to ensure that the blasts or streams of compressed air which are furnished by the pneumatic ejector system can propel successive articles into the inlet of the pneumatic conveyor at a relatively high frequency. Furthermore, the patented apparatus employs a mechanism which can move the sealing member away from the rotary conveyor in order to afford access to the station for propulsion of successive articles of the series into the pneumatic conveyor. This renders it possible to remove a damaged or misaligned article within a relatively short interval of time.
A drawback of the patented apparatus is that the rotary conveyor is frictionally engaged by the sealing member. This can generate substantial amounts of heat and the abutting surfaces of the rotary conveyor and of the sealing member are subject to extensive wear. Furthermore, the output of the patented apparatus is limited, i.e., the upper limit of the frequency at which successive articles are propelled into the pneumatic conveyor is relatively low.